I wanted to pop back in here and give a quick mention that I have been recently investigating using the CnCNet client and Ares myself and made a post over on PPM about how that project's gone. I used most of the source files from 2.0psi but started from a clean rules ini and copied things over individually. It's worked pretty well all things considered but the original country array was a bit of a mess so I ended up redoing that in a way a bit more friendly with the CnCNet Client.
That's not super great for campaign compatibility though and turned out to be a bad idea. I originally thought it was a necessity for the client, but I did just take a look at how Twisted Insurrection is set up and think I could have set it up to work just fine with the original array. With that said, I'll probably scrap the mess I have so far and start fresh. I'm a bit split on where I want to go with it though. I could try for a straight 2.0 conversion, starting with the 2.0 rules and hunting around for NPatch holdovers to convert to Ares or otherwise rework as best I can.
However, I am now leaning a bit more toward a reimplementation. The reason being that one of my hopes for after the 2.0 conversion was to restore the original RA2 and YR campaigns to work with it. That could still be done but it occurs to me that it might be less work to restore the original Mental Omega campaigns to work with something that was built with original game compatibility in mind than to go back and rework all the old missions to work with Mental Omega. That might drift into being more of its own thing though so I don't know.